Some Drew lines originate in England, others in Ireland. There may even be some which originate in Scotland. In tracing y-DNA, it can become confusing when unexpected matches occur, involving lines from two of these countries. The answer will most likely involve an early movement of a Drew ancestor, generally from England (often Devon) into Ireland. This doubtless occurred during "The Plantation" period under Cromwell. Here is a link that indicates there were Drew's moving from Devonshire England during the reign of Elizabeth the First.